ATAAA repeat upstream of glutathione S-transferase P1 and prostate cancer risk.

Objectives: Expression of glutathione S-transferase pi (GSTP1), a detoxification enzyme that also binds steroid hormones, is diminished or absent in human prostate tumors possibly because of promoter hypermethylation. Upstream of its promoter is a polymorphic ATAAA repeat of unknown functional significance. We evaluated whether this polymorphism is associated with prostate cancer.

Modification of BRCA1- and BRCA2-associated breast cancer risk by AIB1 genotype and reproductive history.

Women who have inherited a germ-line mutation in the BRCA1 or BRCA2 (BRCA1/2) genes have a greatly increased risk of developing breast cancer compared with the general population. However, there is also substantial interindividual variability in the occurrence of breast cancer among BRCA1/2 mutation carriers. We hypothesize that genes involved in endocrine signaling may modify the BRCA1/2-associated age-specific breast cancer penetrance.

Evidence that the CAG repeat in the androgen receptor gene is associated with the age-related decline in serum androgen levels in men.

In men over 30 years old, serum levels of testosterone (T) decrease with age. A shorter polymorphic CAG repeat length in exon 1 of the androgen receptor (AR) gene is associated with higher transcription activation by the AR. We determined the number of CAG repeats for 882 men aged between 40 and 70 years from the Massachusetts Male Aging Study (MMAS).

CAG repeat within the androgen receptor gene and incidence of surgery for benign prostatic hyperplasia in U.S. physicians.

Background: CAG repeat length in exon 1 of the androgen receptor (AR) gene correlates inversely with transcriptional transactivation activity of the AR. Men with shorter AR CAG repeat lengths are at higher risk of prostate cancer. Because benign prostatic hyperplasia (BPH) is an androgen-dependent condition, we examined the hypothesis that a shorter AR gene CAG repeat length increases the risk of developing of BPH.

Modification of BRCA1-associated breast cancer risk by the polymorphic androgen-receptor CAG repeat.

Compared with the general population, women who have inherited a germline mutation in the BRCA1 gene have a greatly increased risk of developing breast cancer. However, there is also substantial interindividual variability in the occurrence of breast cancer among BRCA1 mutation carriers. We hypothesize that other genes, particularly those involved in endocrine signaling, may modify the BRCA1-associated age-specific breast cancer risk.